1. Field of the Invention
The invention relates to a device for applying a pasty product, in particular a cosmetic product such as lipstick, presented in the form of a stick and slidably mounted in a case.
Such a stick of lipstick must be friable and is, for this reason, usually of a relatively soft consistency; this entails difficulties joining it to a support such as a cup for carrying the stick with a view to its application to the lips. Thus shocks during carriage, or vibrations during use, may cause the stick to break off at the level of the cup. Indeed, in most of the devices for the application of lip products, a more or less extensive play of the cup in the case may be observed. During the carriage of the case, for example in a handbag or during its use, the stick sways to and fro which may lead to its becoming disconnected from its support.
2. Description of the Related Art
It is known, in particular from FIG. 19a of EP-A-0 658 325, to provide a device aiming to reduce the vibrations of the stick during its use. This device comprises: a tubular element with slides, a cup intended to receive the stick of the product and being slidably mounted in the tubular element with two stubs of the cup engaged in the longitudinal slides; a cylindrical shell whose internal side is provided with helical grooves and which is fitted on the tubular element so as to be free for rotation relative to the tubular element, the stubs of the cup being engaged in the helical grooves of the shell; and means for providing soft friction between the cup and the tubular element, these friction means comprising at least one tongue which is flexible in the radial direction, is provided on the tubular element, and is capable of cooperating with a bearing surface of the cup.
However, the solution proposed by this document poses problems in its practical use, since the radial space left for the making and the deformation of the flexible tongue is reduced between the external sleeve and the cup. This space has a precise play necessary to ensure the guided sliding of the cup in the tubular element. Too great a deflection of the flexible tongue during the sliding of the cup in the tubular element, due to imperfections of the molding of the cup and/or of the tongue and/or of the tubular element, leads irretrievably to the jamming of the cup.
FR-A-1 501 043 describes a mechanism for a lipstick comprising a cup provided with diametrically opposed stubs and each engaged, one the one hand in an axial slide, and on the other hand in a helical groove. Each stub is provided with a slot capable of imparting to it radial elasticity capable of permitting friction of the stub either in the slide or in the helical groove. However, this arrangement does not make it possible to compensate for large dimensional variations between the stub and the slide, and the elasticity of a split stub is generally insufficient to ensure suitable friction.
In addition, from U.S. Pat. No. 2,777,572 there is known a mechanism for a lipstick comprising a tubular element provided with a first axial slot acting as a slide for a stub of a cup for the product. A second slot, parallel to the first, defines a tongue which becomes retracted inside the tubular element so as to rub elastically in a radial direction of the tubular element, on the side edge of the cup. Although friction on the cup can be obtained in the median zone of the tongue, vibrations of the cup in the high or low positions cannot be reduced or suppressed. Moreover, this arrangement produces an off-centering of the cup on the opposite side to the tongue, which has an adverse effect on the appearance of the device.